1. Field of the Invention
This invention relates to a hard disk substrate processing machine useful for treating surfaces of hard disk substrates for magnetic disks or the like.
More specifically, the present invention concerns a grinding/texturing/burnishing/polishing/wiping machine employing a cartridge which accommodates a grinding, texturing, burnishing, polishing or wiping tape for processing the surfaces of hard disk substrates, the machine including a tape drawing mechanism for drawing out the processing tape in the cartridge to a predetermined position on the machine, a substrate holder mechanism for holding and rotating a hard disk substrate, and a tape pressing mechanism for pressing the tape against the hard disk substrate, automatically loading the tape into a predetermined path of travel in a facilitated manner to improve the working efficiency and productivity of the surface treatment operation.
2. Prior Art
As a memory medium for computers, for example, circular magnetic disks which permit random access have been in wide use, and above all the so-called hard disks using a substrate of hard material such as an aluminum alloy, glass sheet, plastics or the like are now in popular use for fixed disks or external disks because of their excellent response and large memory capacity.
The hard disks which have a data recording and reproducing magnetic layer formed, for example, on an aluminum alloy substrate for magnetic disk, are used at a high speed rotation for recording and reproducing information in a multitude of concentric tracks.
In case of magnetic disks of this sort, the substrate surfaces are required to have fine irregularities or certain surface coarseness before formation of the magnetic layer. Namely, the fine surface irregularities are greatly related with the performance quality in travel or motion and durability of the magnetic disks as well as with the improvement of the adhesion of the magnetic layer formed on the substrates.
For forming such fine surface irregularities, there have been introduced various means, including the so-called processing tape having abrasive grains fixed thereon, the dry etching by a bombardment treatment or the like, wet etching etc. Among these, the processing tapes which have a higher processing speed than other means have been generally adopted for forming fine surface irregularities in the circumferential direction of the disks.
When processing magnetic disks by the use of a tape, it has been the conventional practice to set the tape in position by drawing out part of the tape which is simply wound on a reel or the like and threading it manually through and around a large number of guide rollers which are located in predetermined positions on a grinding machine. Then, the tape which is continuously fed from the reel is held in contact with a hard disk substrate which is rotated about its axis, for treating the surface thereof.
In this connection, it has been the general practice to thread the processing tape manually around a large number of guide rollers to set the tape in a predetermined path of travel, but this job is very complicated and time consuming. Besides, the manual tape threading operation often gives rise to the problem of false tape setting, and handling of the tape itself is not easy.